This invention relates to a method for stabilizing irregular structures such as rock structures in mines as well as other rock, concrete and molding tool structures. The invention also relates to weather resistant and anti-corrosive polyurea coating materials for stabilizing irregular structures.
Membrane coatings have been developed for the purpose of partially replacing the screen component of bolts-and-screen or thin shotcrete layers in mines. Such coatings are used primarily in underground hard rock mines for the provision of rapidly-deployable area support coverage.
One such coating material Mineguard(trademark), described in PCT/CA91/00223, is a polyurethane polymer coating which forms a conventional plastic membrane on selected surfaces. Other types of polyurethane coatings that form thin membranes on certain surfaces are described in U.S. Pat. Nos. 4,748,201, 4,748,192 and 4,738,989.
While some of these aforementioned types of polyurethane coatings have been used for stabilization of rock structures in mining, these coatings are thin and provide only limited support and strength to certain structures. Such coatings don""t adequately fill cracks, crevices and fractured ground without repeated time-consuming and expensive applications. Furthermore, these polyurethane coatings are also conventionally applied to form a thin membrane cover and do not have widespread applications in other fields.
There has not been provided an effective rapid method using a particular polyurea or polyurethane type coating material that can effectively produce a cohesive coating material which acts to stabilize rock and concrete structures or other irregular structures as well as provide durability, weatherability and anti-corrosion properties to the structure. Furthermore, there is presently no polyurea or polyurethane type mesh or film coating that provides the necessary characteristics to effectively stabilize various irregular structures and that has general use in the field of mining construction and composite parts manufacturing.
There is therefore a need to develop a simple, rapid and cost efficient method for stabilizing irregular structures such as rock and concrete structures that obviates at least some of the shortcomings of the prior art.
The present invention relates to a fast reacting method of making a polyurea coating material for stabilizing irregular structures and the polyurea coatings so prepared. The method and the polyurea coating materials have widespread use in the stabilization of irregular structures such as irregular rock, concrete and molding tool structures.
In accordance with an aspect of the present invention is a novel method for stabilizing irregular rock, concrete and molding tool surfaces and structures in general. The method of the present invention is simple to use and effectively provides in one aspect a cohesive unwoven type fabric that can be applied to uneven and irregular surfaces to create a consolidating and stabilizing mesh or webbing type of membrane. As such, the method provides a fibrous weather resistant and anti-corrosion type mesh that has the ability to bridge large gaps and cracks in irregular structures especially rock and concrete structures. The fibrous mesh can withstand large fluctuations in temperature and precipitation with minimal deterioration or effect on its stabilizing properties on the applied underlying structures.
In the first aspect, the method is preferably used to provide a fibrous mesh that acts to effectively, rapidly and safely stabilize rock structures particularly in hard rock mining. The fibrous mesh can effectively fill large gaps in various rock and tunnel structures. The method can also be used to stabilize rocky hillsides adjacent highways to prevent falling rocks and rock slides. The method also has general use in the construction industry in order to stabilize any type of concrete or concrete/rock structure.
The method of the present invention in this aspect, allows for air and water permeation therethrough when the material is applied as a mesh or webbing.
In another aspect of the present invention, the method can be altered to provide a plastic film type of polyurea coating which is impermeable to water and air. In this aspect, the plastic film coating has application in the field of mold tooling especially for making molds and the like. In a further aspect of the invention, the method can provide for a more matted geotextile type mesh product that has use in the landscaping and road building trades.
In yet still a further aspect, the method can provide a xe2x80x9cjellyxe2x80x9d state that is useful as an adhesive. With respect to any aspects of the invention, the resultant polyurea material provided as a fibrous mesh, matted mesh, plastic film or jelly state can be provided as a layered or multi layered structure incorporating the various formats of polyurea material.
According to an aspect of the present invention is a polyurea spray system for providing a stabilizing polyurea material.
According to a further aspect of the present invention is a polyurea spray system for providing a stabilizing polyurea fibrous mesh material.
According to still a further aspect of the present intention is a polyurea spray system for providing a stabilizing polyurea plastic film material.
According to yet a further aspect of the present invention is a polyurea spray system for providing a stabilizing polyurea geotextile matted material.
According to another aspect of the present invention is a polyurea spray system for providing a stabilizing polyurea foam material.
According to still another aspect of the present invention is a polyurea spray system for providing a stabilizing polyurea jelly material.
According to an aspect of the present invention is a method for stabilizing irregular rock, concrete and molding tool structures, the method comprising
concurrently heating and mixing a mixture of polyoxypropylene diamine with an aromatic diamine liquid;
mechanically purging the mixture under pressure with an isocyanate;
applying the purged mixture to a desired irregular structure.
According to an aspect of the present invention there is a method for stabilizing irregular rock and concrete structures, the method comprising:
concurrently heating and mixing in about a 2:1 to 1:1 ratio, a mixture of polyoxypropylene diamine with an aromatic diamine liquid;
mechanically purging the mixture under pressure with an isocyanate to create a fibrous mesh, the mesh being applied to a desired irregular rock and concrete structure.
Preferably, the mixture is heated from about 90xc2x0 F. to about 115xc2x0 F. and purged under pressure from about 1000 psi to about 3500 psi In this manner, optimal fiber sizes and lengths are accomplished to enmesh fill in gaps between and stabilize irregular rock and concrete structures.
According to another aspect of the present invention is a method for stabilizing irregular rock, concrete and molding tool structures, the method comprising:
concurrently heating and mixing in about a 2:1 to 1:1 ratio, a mixture of polyoxypropylene diamine with an aromatic diamine liquid;
mechanically purging the mixture at over about 1000 to 3500 psi with an isocyanate to create a plastic film, the plastic film being applied to a desired irregular structure.
Preferably in this aspect, the mixture is heated from about 140xc2x0 F. to 170xc2x0 F. In this manner, under the appropriate high pressure the irregular rock, concrete or molding tool surfaces are stabilized within a plastic film type of coating which is impermeable to air and water. In accordance with this aspect, other materials can be added to the purged mixture to alter the final plastic polyurea film material. Such materials include but are not limited to fire-retardants, ceramic microspheres, rubber crumbs and the like.
According to another aspect of the present invention is a cohesive polyurea mesh for use in consolidating and stabilizing irregular rock concrete and molding tool structures.
According to a further aspect of the present invention is a fibrous polyurea mesh for stabilizing and supporting irregular rock and concrete structures, the mesh comprising:
elongate fibers comprising a mixture of polyoxypropylene diamine and aromatic liquid diamine;
said fibers having a high tensile strength; and
said fibers being weather resistant and anticorrosive.
According to still a further embodiment of the invention is a cohesive fibrous mesh comprising strands of inorganic polymers for stabilizing irregular surfaces.
According to yet a further embodiment of the invention is a cohesive fibrous mesh comprising flame retardant strands of inorganic polymers and additionally comprising a flame retardant.
Preferably, the mesh is made of a polyurea material vehicle when dry provides a durable, damage resistant, hard protective surface which is moisture resistant, has a high tensile strength and is non-flammable.
According to another aspect of the present invention is a polyurea geotextile mat for use in consolidating and stabilizing irregular rock, concrete, and dirt surfaces.
According to another aspect of the present invention is a polyurea plastic film for use in stabilizing molds and molding tool structures.
According to another aspect of the present invention is a polyurea foam for use in consolidating and stabilizing irregular rock, concrete, molding tool and dirt surfaces and other composite structures and manufactured parts.